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If your printer is an "all-in-one" model, it can scan. Some other printer models can scan as well, though you'll need to check the printer's documentation or product page to ensure that this is the case. . Most Canon printers that can scan will also be able to connect wirelessly via a touch-screen panel, but you may need to connect your printer to your computer via USB cable. Press the printer's "On" button. If the printer won't turn on, make sure that it's connected to a working power source. Lift up the scanner's lid so that you can see the glass bottom of the scanner.  If your Canon printer has an all-in-one paper feeder, insert your document into the tray instead. You can look at the symbol on the tray to see how to insert the paper. Consult your Canon's instruction manual if you can't figure out how to use the built-in scanner. You should see markings next to the glass bottom; these usually indicate how the document should be oriented in the scanner. Make sure that it is firmly shut before you scan your document.
Make sure that your Canon printer can scan. Connect your printer to your computer Turn on your printer if necessary. Open the scanner. Place your document face-down in the scanner. Close the scanner lid.